Malicious PDF — malware analysis report

Static analysis result for SHA-256 70d1bf78947eb14b…

MALICIOUS

PDF

76.3 KB Created: 2021-09-06 23:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b5dc8804b743425ebca9d0e20620e33b SHA-1: 9f930c57f398ed9c6f3a54bf93eb468b6197bba6 SHA-256: 70d1bf78947eb14baf1bc742671684f40ab7260e58c003b8c1b44f8f5a822f23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The primary purpose seems to be distributing malicious content or manipulating search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://x-software.cz/data/file/27975289083.pdf In PDF document text
    • http://musiclivemarsala.com/userfiles/files/nabepexujuzijuti.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/rokipekegaxis.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-06-09/images/files/92037512772.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdd01c98877---zedex.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/98090059181.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/zegipawedon.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac72dc3017a---70291470950.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/69077581824.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cca24627c1---20735868507.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1630308431_1.pdfIn PDF document text
    • http://skikk.eu/app/webroot/files/userfiles/files/genejaj.pdfIn PDF document text
    • http://kedehg.com/ckfinder/userfiles/files/30190860778.pdfIn PDF document text
    • http://hermandadperdon.es/userfiles/file/pafiporalixiki.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/jetol.pdfIn PDF document text
    • https://cafe-malaysia.com/contents/file/difimi.pdfIn PDF document text
    • https://perfecthospital.net/FCKeditor/file/sumakomupe.pdfIn PDF document text
    • http://bbfrontedelmare.com/userfiles/files/69178608481.pdfIn PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/dajitaxesimoset.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/293g9ls16ri9d9enib61t2h7fd/55612954116.pdfIn PDF document text
    • http://kppzp.pl/userfiles/file/69489352347.pdfIn PDF document text
    • https://benhgout.net/uploads/Files/file/lubobojem.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/2c50bc29a9986ef595a0ca52a4972c3f/xefulafifanetobam.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/momitedenipa.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/nizilinirudi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=create+pdf+file+in+html+javascriptPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c5b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ddd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD0 10992 bytes
SHA-256: 37a6366a827dac35041aae63308909a2c8bc297e5a6cea6c3bcd7b828c512371
font_02_sfnt_off0000f717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF717 17132 bytes
SHA-256: c7a7350eef8f4eec20768f03a5a51f9d2e1f4b994011ce0426d8a2ca7476d11d